Electric timepiece

ABSTRACT

IN AN ELECTRIC TIMEPIECE, THE COMBINATION OF A FLEXIBLE RESONATOR HAVING A VIBRATING FLEXIBLE BLADE FOR DRIVING A RATCHET COUNTING WHEEL, IN A STEP BY STEP MANNER THROUGH A TRAIN INCLUDING A PAWL, A CIRCULAR GUAGE OF A SMALLER DIAMETER THAN THE RATCHET COUNTING WHEEL DIAMETER FOR FUNCTIONING IN LIEU OF THE RATCHET COUNTING WHEEL IN THE SETTING AND ADJUSTING OPERATIONS WITH THE PAWL BEING CONTACTABLE WITH THE GAUGE WHEREFOR THE TENSION OF THE PAWL CORRESPONDS TO A VALUE SUFFICIENT TO SATISFACTORILY OPERATE THE COUNTING MECHANISM.

Nov. 2,1971 R. CHOPARD ETAL ELECTRIC TIMEPIECE 3 Sheets-Sheet 1 FiledFeb. 27, 1970- INVENTOR. Romy CHOPARD and Rene BESSON Nov. 2, 1971 RCHOPARD 7 ET AL ELECTRIC TIMEPIECE 3 Sheets-Sheet 2 Filed Feb. '27, mo

INVENTOR Ha'm y CI-IOPARD U 5 u \m.

and Hana BETDSON BY a Che/1M5 7121/1/02 s Sheets-Sheet z ELECTRICTIMEPIECE R. CHOPARD Nov.'2, 1971 Filed Feb. 27, 1970 United StatesPatent Office 3,616,636 ELECTRIC TIMEPIECE and Rene Besson, Neuchatel,Switzerland, assignors to Ebauches S.A. Filed Feb. 27, 1970, Ser. No.15,028 Claims priority, application Switzerland, Mar. 17, 1969, 3,925/69Int. Cl. G04c 3/00 Remv Chopard US. Cl. 58-23 Claims ABSTRACT OF THEDISCLOSURE The present invention provides an electric timepiece with aflexure resonator in which at least one flexible vibrating blade drivesstep by step, by the intermediary of a pawl, a ratchet counting wheel.

This electric timepiece is characterized by the fact that it comprises acircular gauge of a diameter smaller than that of the counting wheel,which can be substituted for this counting Wheel for setting andadjusting operations, the arrangement being such that, when the pawl isjust in contact with the gauge, without exerting radially thereon anypressure, the tension of the pawl, when the counting wheel is again putinto place, corresponds to the value necessary for satisfying operationof the counting mechanism.

The drawing shows, by way of example, one embodiment of the invention.

FIG. 1 is a plan view, from above, of the movement of an electricwrist-watch.

FIG. 2 is a sectional view along line II-II of FIG. 1, at an enlargedscale.

FIG. 3 is a plan view, from below, of a portion of the movement.

FIG. 4 is a sectional view of a detail, along line IVIV of FIG. 1, at anenlarged scale, and,

FIG. 5 is a sectional view of a detail, also at an enlarged scale.

The watch movement represented comprises a base plate 1 (FIGS. 1 and 2)carrying the conventional mechanical elements, especially the gearingwhich, on the other side, is carried by a gearing bridge 2, visible inFIG. 2 only, secured to the base plate by screws 3 provided with conicalbearing surfaces.

The frame of the movement also comprises a second base plate, designatedby 4, removably secured to the base plate 1, on the upper face thereof,above the gearing bridge 2, and held in place by means of securingscrews 5 (FIG. 1).

This base plate 4, the shape of which has been represented by a heavyline in FIG. 1 for clarity, is represented as being viewed from below inFIG. 3. It carries the driving and regulating devices, that is to saythe mechanical and electrical portions of the movement of the watch.

This driving-regulating device comprises a fiexure symmetrical resonator6, secured to the base plate 4 by at their free ends, the movableelements 8 of a trans- Patented Nov. 2, 1971 ductor, the fixed elementsof which are constituted by two driving windings 9. The flexible arms 6aof the resonator 6 carry in the neighborhood of their free ends, andsecured by pins 10, rigid arms 11 ending in enlarged portions 11a,functioning as balanced weights, and which themselves carry balancingmasses 12. These latter, which have the shape of three arm stars, areasymmetric since one of their arms is provided with a notch 13. Thus, byrotating these masses, one modifies the position of the center ofgravity of each of these two symmetric portions of the resonator, thuspermitting adjustment of its frequency. The two enlarged portions 11a ofthe rigid arms 11 are each provided with a graduation 14 (FIG. 1), thuspermitting control of the position of the masses 12 and facilitating thesetting operations.

The sustaining of the oscillations of the resonator 6 is effectedelectrically by means of a transistorized electronic circuit fed by anelectric battery 15 (FIG. 1) located in an are shaped recess 16 providedin the base plate 4 and in a circular recess 17 provided in the baseplate 1. These two recesses are coaxial when the two base plates areassembled to each other, thus providing a circular partition intended toreceive the battery 15 which occupies, substantially, the whole heightof the movement.

The battery is maintained in place by two straps which also insure theelectric connection of the battery with the electronic circuit; thesetwo straps are constituted by elastic blades, one of which, designatedby 18, is secured to the base plate 1 by a screw 19, and the other ofwhich, designated by 20, is secured to the base plate 4 by meanshereafter disclosed. The strap 18 insures the connection of the positiveterminal of the battery 15 with the mass of the movement and the strap20 insures the connection of the negative terminal of the battery withone of the terminals of the electronic circuit.

The electronic sustaining circuit of the oscillations of the resonatorcomprises two different electronic blocks a small plate 21 or 22respectively, secured to the base plate 4, under the latter, by means ofscrews 23. These small plates have been shown by heavy lines in FIG. 3to help increase the clarity of the drawing.

Each of the electronic blocks comprises one of the two driving windings9 and a portion of the electronic components of the circuit; one of theblocks comprises pick-up winding combined with one of the two windings9. The two electronic blocks, the small plates 21 and 22 of which aremade of insulating material, are constituted by circuits which areachieved, by cutting a conductive metallic sheet so as to constitute agate, by embedding this gate into the insulating material of the smallplates, as a moulding operation, then by cutting the edges of the gateso as to separate the constituting elements of the circuit; theelectronic components are welded to the gate after the moulding and thecutting of the edges thereof.

FIG. 3 shows, by way of example, three metallic tongues 24 whichconstitute the terminals of three constitutive elements of the circuit,protruding laterally on the edge of the small plate 21, and a metallictongue 25 constituting a connecting terminal of the circuit, protrudinglaterally on the edge of the small plate 22.

The strap 20, maintaining battery 15 in situ and insuring the electricconnection of the negative terminal of the battery, is riveted at 26(FIGS. 1 and 3) to the small plate 21 and is welded at one of theelements of the gate constituting the circuit.

So far as the connection of the circuit with the positive terminal ofthe battery is concerned, which positive terminal, as stated hereabove,is the mass, it is insured by a pin 27 (FIGS. 1 and 3) carried by theabove mentioned metallic tongue 25, which is normally in contact with anelastic blade 28 carried by the base plate 4. This blade passes in anotch provided in a bent portion 29a of a lever 29 mounted on the baseplate 4 and guided in its displacements, according to the arrows 30 ofFIGS. 1 and 3, by two pins 31 carried by the base plate 4 and which passthrough elongated openings 32 of this lever.

This latter is provided with a fork shaped portion, between the arms 2%of which is engaged a pin 33 (FIG. 1) carried by the setting-lever ofthe movement, not shown. When the setting pin, designated by 34 (FIG. 1)is moved longitudinally, the pin 33 moves along the direction of arrow35, thus producing the displacements of the lever 29 in the direction ofthe arrow 30, the return of the lever in the reverse direction beinginsured by the elastic blade 28, serving as a return spring.

The arrangement is such that, when the setting stem occupies its restposition, in which it is entirely pushed, (position represented in thedrawing), the blade 28 is in contact with the pin 27, closing theelectric sustaining circuit of the oscillations of the resonator; it isthe same when the setting stem 34 occupies its intermediary position ofdate setting of a date indicating element, not represented, owing to theplay of the pin 33 between the arms 29b of the fork of the lever 29,while, when the stem 34 is entirely pulled, in a setting position, thelever 29 is displaced towards the center of the movement, against theresilient action of the blade 28, that separates this blade from the pin27 and thus interrupts the feeding of the sustaining circuit.

The counting of the oscillations of the resonator 6 is effected by meansof a ratchet wheel 36 provided with a very fine toothing, rotatingbetween the base plate 4 and a small plate 37 (FIG. 3) secured under thebase plate 4 by two screws 38; the shape of this small plate has beenshown in heavy line in FIG. 3 to help the clarity of the drawing.

A pawl 39, secured at 40 on one of the portions 11a of the resonator 6,acts on the wheel 36 for rotating it by one tooth upon each oscillationof the resonator. The other portion 11a of the resonator carries a pin41 insuring the balancing of the pin 40.

A second pawl, i.e. a retaining pawl, designated by 42, acts on thewheel 36. This second pawl is carried by a small plate 43 submitted tothe action of a screw 44, screwed in a stud carried by the base plate 4,this screw acting laterally on the small plate for maintaining itapplied, by a circular notch thereof, against a pin 45, constituting ajournal, carried by the base plate 4, and for maintaining an elastic arm43a of the small plate applied against a pin 46 carried by the baseplate 4.

The small plate 43 is prevented from being lifted on the one hand by ahead a provided on the pin 45a and on the other hand by a head 47aprovided on a second pin, designated by 47, of smaller sectional sectionthan the pin 45, engaged with play into an opening 48 having the shapeof a button-hole, provided in the small plate. The portion of greaterdiameter of the button-hole 48 permits the head 47a of pin 47 to passthrough in view of the mounting and dismounting of the small plate.

The arrangement as disclosed permits modifying, by means of the screw44, the position of the retaining pawl 42, and adjusting thereby, withhigh precision, the relative position of the two pawls, the driving pawl39 and the retaining pawl 42, and thus their dephasing.

Owing to the type of mounting of the small plate 43, no articulatingplay is produced, the small plate permanently bearing against pin 45under the effect of its elastic arm 43:: and of the screw 44.

The radial pressure exerted by the two pawls 39 and 42 on the countingwheel 36 has also to be adjusted very precisely.

For this purpose, the movement is provided with a calibrated gauge 49(FIGS. 4 and 5) located, when not used, in a circular partition 59provided in the base plate 4, closed by the base plate 1 when themovement is mounted.

The adjustment of the pressure of the pawls on the counting wheel iseffected when the base plate 4 is separated from the base plate 1. Thegauge 49 is then accessible and can be withdrawn from the partition 50for engagement in the bore, designated by 51, 0f the base plate 4containing the upper bearing, designated by 52, of the counting wheel36, after this wheel has been removed (FIG. 5). The height of the bore51 is sufficient to permit engagement of an extension 49a of the gaugein the bore below the bearing 52. The extension 49a is annular, havingthe shape of a collar, so as to be slightly resilient and thereby toallow frictional engagement in bore 51.

The diameter of the gauge is very slightly smaller than that of wheel36, the difference being such that, when the pawls 39 and 42 are just incontact with the gauge, without exerting thereon any pressure, thetension thereof, when the counting wheel 36 is substituted to the gauge,has the desired value.

The gauge 49, in reserve in the partition 50, is thus always at thedisposal of the repairman. This gauge is provided, besides the collar49a by means of which it is engaged either into the bore 51 of the baseplate 4 or into a circular recess 53, of same diameter as the bore 51,provided in the bottom of the partition 50, with a central button 4%,situated on the opposite face to the one provided with the collar 4911,which permits engagement by means of tweezers, for manipulation thereof.

The transmission of the intermittent rotative movements, step by step,of the ratchet wheel 36 to the indicating elements of the watch, i.e. tothe hands 54, 55 and 56, respectively of hours, minutes and seconds, isinsured by a pinion 57 rigid with the wheel 36 (FIG. 2) meshing with awheel 58 rigid with a pinion 59 engaged, with a very slight play, in abearing 60 carried by the small plate 37; the lower spindle of theelement 58-59 is carried, when the movement is mounted, by a bearing 61itself mounted on the base plate 1.

The pinion 59 meshes with a wheel 62 axially pressed, by an archedelastic washer 63, against a pinion 64 mounted on seconds shaft, at thecenter of the movement designated by 65.

The friction coupling constituted by the elastic washer 63 and theelements which are associated therewith ensures the protection of thecounting ratchet mechanism 39-36 which could be damaged if a reversedirection effort were applied to the counting wheel 36, as for examplewhen the seconds hand is put into place.

Wire spring 66 acts on a pulle 67 mounted on the shaft and serves as abrake of the seconds hand.

The pinion 64 drives a wheel 68 axially pressed by an arched elasticwasher 69 against a disk 70 rigid with a pinion 71 rotatably mountedbetween the base plate 1 and the gearing bridge 2.

The friction coupling constituted by the elastic washer 69 and theelements which are associated therewith operates like the indenting of aconventional watch and permits the setting of the watch without exertingany action on the regulating elements.

The pinion 71 meshes with the minutes wheel, designated by 72, rotatablymounted on a sleeve 73 carried by the base plate 1 and which controls,by the intermediary of the conventional dial-train, not represented, thehour wheel designated by 74.

The general arrangement of the movement, by modules, one of which, thatof the base plate 1, comprises the conventional mechanical elements ofthe watch, and the other of which, that of the base plate 4, comprisesthe driving-regulating device including the electric er tion, is veryadvantageous from the point of view of repairing the several elements,of their mounting, of the setting and of their assembling.

As a matter of fact, this arrangement, especially flexible, permits themounting of each module separately and the testing before assembly.

For instance, any alteration of the counting ratchet device is therebyprevented, which could occur in spite of the friction coupling of thespring 63, when the hands of the watch are put in place or duringaccidental grazings during the mounting operations.

One can even put the conventional portion into the casing of the watch,i.e. the base plate 1, provided with the gearing bridge 2 and all themechanical elements carried thereby, before the driving regulatingmodule be assembled thereto, which is constituted by the base plate 4and all the mechanical and electric elements carried thereby. 1

This arrangement permits moveover the repairer to open the watch, toWithdraw the battery therefrom, to withdraw the module of the base plate4 and to handle it per se, for instance for changing one or the other ofthe electronic blocks, without touching the resonator 6 and withouthaving to make again any setting of the counting ratchet device 39-66.

What we claim is:

1. Electric timepiece with a flexure resonator in which at least avibrating flexible blade drives in a step by step manner through theintermediary of a pawl a ratchet counting wheel characterized by acircular gauge of a diameter smaller than the diameter of the countingwheel so as to be substituted for the counting wheel for setting andadjusting operations, the arrangement being such that,

when the pawl is just in contact with the gauge, without '3 correspondsto the value necessary for a satisfying operation of the countingmechanism.

2. Electric timepiece as claimed in claim 1, characterized by thecounting Wheels having a bearing located in a bore of an element of theframe of the movement, the height of which is higher than the height ofthe bearing in such a way that a circular extension of the gauge can beengaged into the bore below the bearing, the gauge being then in theposition normally occupied by the counting wheel.

3. Electric timepiece as claimed in claim 1, characterized by the factthat an element of the frame of the movement is provided with a circularrecess in which is located the gauge when not in use.

4. Electric timepiece as claimed in claim 3, characterized by the factthat the bottom of the said recess is provided with a central circularhole of same diameter as the bore, into which engages the centralextension of the gauge which is thus maintained in place in the recess.-

5. Electric timepiece as claimed in claim 2, characterized by the factthat the said circular extension of the gauge is annular so as to beslightly resilient, in order to be able to engage itself frictionally inthe said bore.

References Cited FOREIGN PATENTS 1,528,337 6/1968 France 58-230 RICHARDB. WILKINSON, Primary Examiner E. C. SIMMONS, Assistant Examiner

